hypothalamic-pituitary-endocrine gland axes and pineal gland SDL Flashcards
1
Q
outline the hypothalamic-pituitary-adrenal axis
A
- hypothalamus produces corticotropin releasing hormone
- CRH stimulates anterior pituitary to release adrenocorticotropic hormone
- ACTH stimulates adrenal cortex to release cortisol
2
Q
outline the hypothalamic-pituitary-thyroid axis
A
- hypothalamus produces thyroid releasing hormone
- TRH stimulates anterior pituitary to release thyroid stimulating hormone
- TSH stimulates thyroid to produce T3 and T4 (triiodothyronine and thyroxine respectively)
3
Q
outline the hypothalamic-pituitary-gonadal axis and specify both female and male systems
A
- hypothalamus releases Gonadal releasing hormone
- GnRH stimulates anterior pituitary to release Luteinizing hormone and follicular stimulating hormone
- LH and FSH stimulate testicles to release testosterone (male) and estradiol/progesterone (females)
4
Q
describe the location of the pineal gland
A
- located immediately behind the thalamus
5
Q
what is the difference between melatonin and melanocyte stimulating hormone (MSH)
A
Melatonin primarily regulates circadian rhythms and has antioxidant properties, while MSH primarily regulates skin pigmentation and has other physiological effects.
6
Q
what triggers the shedding of the winter coat in horses
A
- daylight length
- temp changes
- hormonal shifts
7
Q
which animals show seasonal anestrus
A
- cats
- horses
- rabbits
NOT dogs, cows or pigs
8
Q
how would you bring a mare out of seasonal anestrus earlier?
A
- light management to mimic longer daylight hours
- hormonal treatment (progestin and gonadotropins)
9
Q
what does the pineal gland do
A
- produces melatonin
- amino acid derivative from tryptophan
- involved in sleep and biological rhythms
- responds to light (produces melatonin when dark and less when light)
10
Q
melatonin and MSH are involved in
A
- seasonal haircoat colour changes
- seasonal haircoat shedding
- seasonal anestrus
